1. Field of the Invention
The present invention relates to a pressure control device for regulating the pressure of fuel supplied from a fuel tank to an engine.
2. Description of the Related Art
In two-wheeled or four-wheeled automobiles, when fuel is supplied from a fuel tank to an engine, a pressure adjustment is made so that the fuel may be supplied under an appropriate pressure. Hereinafter, this pressure adjustment will be referred to as “pressure regulation”. That is, the fuel supply system is provided with a pressure control device for regulating the supplied fuel to an appropriate pressure.
As disclosed in Japanese Laid-Open Patent Publication No. 2009-144686, a known pressure control device is equipped with a seat, a valve seated on the seat to close a supply flow path, and a biasing spring biasing the valve in a seating direction for seating on the seat. The pressure control device disclosed in the Publication No. 2009-144686 utilizes a pressurizing force of the supply fuel fed from a fuel pump, and a back pressure after having fed this supply fuel, whereby the seated state of the valve with respect to the seat is adjusted, and the pressure of the supply fuel is regulated.
In recent years, to achieve an improvement in terms of the starting property of the engine, there is a need that the fuel pressure in the fuel supply path toward the engine be maintained in a high pressure state even in a state in which the fuel pump is not operating.
However, in a pressure control device in the state in which the fuel pump is not operating, the seating of the valve on the seat is likely to be released, resulting in the system being subject to leakage of fuel from the fuel supply path. If fuel leaks from the fuel supply path, it is impossible to maintain the fuel in the fuel supply path in a high pressure state, making it impossible to meet the above-mentioned need.
Therefore, there is a need in the art for a pressure control device that can maintain a fuel pressure within a fuel supply path for supplying fuel to an engine even in a state in which a fuel pump is not operating